This invention relates to heating systems and more particularly to a hot water or steam heating system which includes a supplemental heating coil arrangement.
There are numerous types of heating systems which are generally utilized for indoor heating of buildings. Some of the most common types include the steam heating and hot water heating systems. In both of these systems, a furnace is provided which includes a burner for burning a source of fuel. The fuel source can be gas, oil, or coal. The burner generates heat from the fuel, the heat being applied to an upper chamber in the furnace which contains water.
In the hot water system, the heat is used to heat up the water. Typically, a pump forces the hot water out of the water heater in the upper part of the furnace and through the pipes in the building to heat the various rooms.
A steam heating system works much like a hot water heating system, except that the water changes to steam in a boiler contained in the upper part of the furnace. The steam then passes through the pipes where it gives up its heat to the various rooms and becomes liquid again. The water then flows back into the boiler.
In both these types of systems, the furnace is constructed so that the lower part of the furnace is used to produce the heat by burning the fuel, and the upper part of the furnace is used as the water container where the water is heated or is boiled to form steam.
While both of these systems are commonly utilized, the efficiency of these systems is rather poor. It generally takes a large amount of fuel to generate sufficient heat to heat up or boil the water contained in the upper compartment of the furnace. This is especially a problem when starting up a furnace from a cold start, where it is necessary to heat up all the water to a sufficiently high temperature before any heat will be generated to the various rooms of the building.
At the same time, it has not been feasible to improve this efficiency since a separate compartment is required for the water and a separate compartment is required for the fuel combustion. The storage unit, whether it be in a hot water heater or in a steam boiler, must be securely sealed to prevent any water leaks. The burner section, on the other hand, requires a separate construction of heavy insulation and fire resistant surfaces to retain the heat. Also, it requires suitable air vents, smoke outlets, etc. As a result, two separate compartments have always been maintained to provide for the two separate requirements of these various units. Accordingly, although the two compartments are adjacent, nevertheless, they are separate, and accordingly the efficiency is low.